Apparatus for coating pipe



April 25, 1944. w. F. FOCHA APPARATUS FOR COATING PIPE Filed Oct. 16,1941 INVENTOR 14/418601 7- ATTORNEYS Patented Apr. 25, 1944 APPARATUSroa coa'rnvo P rn William F. Focha, Westfield, N. 3., assignor toWailes, Dove-Hermiston Corporation, a corporation of New YorkApplication October 16, 1941, Serial No. 415,273

'7 Claims.

In my Patent No. 2,288,316, June 30, 1942, I have described apparatusfor coating pipe with hot, liquid bitumen. The apparatus comprisesgenerally a jet ring encircling the pipe and provided with a pluralityof jet orifices extending about its inner face. The hot liquid bitumenis pumped under pressure from an open air-jacketed sump below the ring,and, through the jet orifices, against the pipe in a plurality of fineradial streams, the excess draining back into the sump. The moltenbitumen is poured into the sump at the desired temperature and viscosityand maintained in that condition by means of hot air forced through theannular air-jacket and thence through the air-jacket of the sump. Thering and its connections are supported upon a carriage designed to moveupon the pipe being coated. Although this method and apparatus representa great improvement over prior methods and apparatuses for coating pipewith bitumen, some difiiculty has been experienced in obtaining perfectcoatings on the bottom surfaces of the pipe. Excess bitumen flowing fromthe pipe and dripping from the under surface congeals, formingprojecting teats. Sometimes small craters form between the teats andextend through the coating to the pipe itself. Thus despite the teats,the effective coating on the bottom of the pipe is thinner and of poorerquality than the coating on the top and sides.

I have discovered that by applying a preliminary coating of bitumen tothe under side of the pipe in advance of the coating applied by the jetring, the craters are eliminated, the number of teats considerablyreduced, and a more uniformly coated pipe is produced. I apply thispreliminary coating by means of an auxiliary, multiple jet nozzle lyingin advance of the jet ring but not beyond the forward wall of the sump,through which jets of bitumen are forced upwardly over the under side ofthe pipe along a strip extending about 35 on each side of the center.Bitumen is supplied to the auxiliary nozzle through an upwardly slopingpipe branching from the pump line just below the jet ring.

In the accompanying drawing I have illustrated a preferred embodiment ofmy invention applied to pipe coating apparatus of the type illustratedin my Patent No. 2,288,316. In the drawing Figure 1 is a side elevationof a pipe coating apparatus, in which the auxiliary, multiple jet nozzleof the present invention has been installed, mounted upon a pipe to becoated, and Figure 2 is a transverse section of the apparatus takenalong line 2-2 of Figure 1. In these figures the driving means for thecarriage and the furnace for supplying hot air to the air-jackets arenot shown; nor are the air-jackets shown in any detail.

The jet ring, by means of which the pipe is coated about its periphery,is indicated by the reference character l. This ring receives moltenbitumen from a slump 2 in which is mounted a pump 3 which forces hotliquid bitumen into an annular duct within the ring, through a pluralityof circumferentially spaced orifices and against the pipe ii, in anumber of radial jets the excess draining back into the sump. Thebitumen in the sump and in the duct is maintained in liquid condition bymeans of hot air chambers with which both the sump and thering areprovided, as set forth in some detail in my co-pending application. Thejet ring and sump are mounted upon a carriage 5 supported and driven bytwo pairs of wheels 6, designed to run upon the pipe as a trackway. Themovement of the car riage, as it is illustrated in Figure 1 is to theright so that the wheels roll over the uncoated pipe. The foregoingconstitutes a brief description of the pipe coating machine illustratedin my Patent No. 2,288,316. In accordance with the present invention Ihave provided an auxiliary, multiple jet nozzle l extending forwardly ofthe jet ring and below the pipe t and supported by a pipe 8 slopingdownwardly from the nozzle to a point of juncture with the pump line.The nozlze l is provided with a plurality of upwardly and backwardlyfacing orifices through which jets of bitumen are squirted upon thelower face of the pipe over an are extending approximately 35 on eitherside of the vertical center line of the pipe, as shown most clearly inFigure 2. The hot liquid bitumen is forced through the orifices of thenozzle by means of the pump 3.

Although the jet ring and sump are provided with hot-air jackets tomaintain the bitumen in liquid condition and prevent clogging of the jetorifices of the ring, I have found that the auxiliary jet nozzle neednot be air-jacketed. 'In its sheltered position below the pipe and abovethe sump, the auxiliary nozzle does not tend to clog and when the pumpis stopped any bitumen in the nozzle and its connections immediatelyflows back into the sump through the downwardly sloping pipe 8. In anyevent, the nozzle and its pipe 8 can be readily detached and cleaned if,for any. reason, clogging should occur.

applied very soon after the preliminary bottomcoat, and as the jet ringapplies a coat around the periphery of the pipe, the bottom is coatedtwice. While it is not absolutely necessary that the location of thenozzle be such that the material is still hot or semi-liquid when thesecond coat is applied, it is desirable for the reason that it tends tomake for better fusion of the two coats of bitumen and does not permitany foreign substance to come between the two applications. By means ofthis double coating it is possible to obtain a substantially uniformthickness of bitumen around the full circumference oi the pipe.

I claim: 7

1. Apparatus for coating pipe with hot liquid bitumen which comprises anannular duct, a pin-- rality of orifices spaced around the duct, anauxiliary nozzle spaced from the annular duct and extending part wayaround the pipe for applying bitumen to the bottom only of the pipe, andmeans for forcing jets of hot liquid bitumen against the pipe throughthe duct orifices and the nozzle.

2. Apparatus for coating pipe with hot liquid bitumen which comprises anannular duct, 9. plurality of orifices spaced around the duct, anauxiliary nozzle spaced from the annular duct and extending part wayaround the pipe for applying bitumen to the bottom only of the pipe,means for forcing jets of hot liquid bitumen against the pipe throughthe duct orifices and the nozzle, and means for eflecting a relativemovement of the pipe and the jets longitudinally of the pipe in such adirection that the auxiliary multiple jet nozzle applies a coat to thebottom of the pipe in advance of the coat applied through the annularduct orifices.

3. Apparatus for coating pipe with hot liquid bitumen which comprises anannular duct, 2. plurality of orifices spaced around the duct anauxiliary nozzle spaced from the annular ductand extending part wayaround the pipe for applying bitumen to the bottom only of the pipe,means for forcing jets of hot liquid bitumen against the pipe throughthe duct orifices and the nozzle,

and a sump for the hot liquid bitumen extending below both the auxiliarynozzle and the annular duct.

a. Apparatus for coating "pip with hot liquid bitumen which comprises anannular duct, a plurality of orifices spaced around the duct, anauxiliary nozzle spaced from the annular duct and extending part wayaround the pipe for applying the bitumen to the bottom only of the pipe,means for forcing jets of hot liquid bitumen against the pipe throughthe duct orifices and the nozzle, and a carriage on which the annularduct and the auxiliary nozzle are mounted for movement along the pipebeing coated.

5. Apparatus for coating pipe with hot liquid bitumen which comprises anannular duct encircling the pipe, a plurality of orifices spaced aroundthe duct, an auxiliary, multiple jet nozzle extending forwardly of theannular duct below the pipe and connected to the annular duct by meansof a sloping pipe, a sump below the duct and nozzle, a pump for forcinghot liquid bitumen from thesump into the duct and nozzle and against thepipe in a plurality of jets, and a carriage on which the duct, nozzleand sump are mounted for movement along the pipe being coated.

6. Apparatus for coating pipe with hot liquid bitumen which comprises aduct extending around the pipe, a plurality of orifices in the duct, anauxiliary, multiple jet nozzle spaced from the duct below the pipe andextending through about 35 on each side of the center of the pipe, andmeans for forcing jets of hot bitumen against the pipe through the ductorifices and the nozzle.

7. Apparatus ior coating pipe with hot liquid bitumen which comprises aduct extending around the pipe, a. plurality of orifices in the duct, ajacket about the duct, means for passing a heating fluid through thejacket for keeping the bitumen in the duct hot, an auxiliary nozzlespaced from the duct below the pipe, and means for forcing jets of hotbitumen against the pipe through the duct orifices and the nozzle.

WILLIAM F. FOCHA.

